The Tissue/Cell Culture Core (TC core) produces in vitro models for study of cochlear development, function, and response to deafening or trauma. The goals of the TC core are to (1) assist investigators in producing cultures for use in their research on the cochlea; (2) assist investigators in genetic manipulation of cultured cochlear cells and tissues using transfection, virus-mediated gene transfer, and the use of genetically modified animals; (3) assist investigators in developing and optimizing new in vitro model systems; (4) train investigators, students, postdocs, residents, and staff in culture techniques and troubleshoot problems; (5) coordinate multidisciplinary experiments among investigators and the Genomics and Histology & Imaging cores, which will use live cultures prepared in the TC core; (6) promote and support collaborations among investigators to use multidisciplinary approaches with in vitro models or parallel in vivo and in vitro models. To these ends the TC core will maintain two well-equipped tissue culture facilities in which production of cultures and training can be carried out. The TC core co-Directors Drs. Steven Green and Marian Hansen have almost unequaled experience in rat and mouse cochlear culture systems including dissociated cell cultures from spiral ganglion, cocultures of spiral ganglion neurons and hair cells, and intact organotypic cochlear explant cultures. The co-Directors have experience in gene transfer into cultured cells by transfection, gene gun, adenoviral and lentiviral vectors, and in manipulating gene expression in cultures from transgenic mice with conditional Cre recombinase expression. Thus, the TC core will be able to achieve the stated goals to assist and train investigators and catalyze pilot projects to develop new methods and establish new collaborations. To further promote information sharing and collaborations, the TC core will conduct classes in TC techniques, in addition to informal training, and participate in the semiannual Center symposia at which investigators will present and discuss research results and techniques. Drs. Robin Davis and Stefan Heller, experts in cochlear culture and auditory neuronal stem cells are members of the P30 external advisory committee who will annually review TC core operation and advise the co-Directors.